The purpose of this training grant is to help establish the candidate's independent research career in the field of psychiatric and behavioral genetics. The candidate has completed clinical training in psychiatry and child psychiatry, and has prior research experience in molecular genetics of simple Mendelian and genomic disorders. The candidate's training will take place in the laboratory of Dr. Wendy Raskind at the University of Washington. Dr. Raskind is part of an established multidisciplinary research team investigating dyslexia. This study proposes to investigate the genetic basis for dyslexia. Dyslexia is a common and complex disorder in which genetics has a significant component. Impaired phonological processing and underlying language processes have been identified as core deficits in dyslexia. Recently, the contributions of attention and executive functioning factors have been increasingly recognized. Attention and executive function deficits are commonly observed in many heritable psychiatric disorders. Dyslexia also demonstrates significant comorbidity with psychiatric disorders of childhood such as ADHD. Studying the genetic basis of attention and executive functioning may help elucidate the genetic underpinnings of additional psychiatric disorders. Although genetic studies of dyslexia can be complicated by a lack of consensus on diagnostic criteria and by genetic heterogeneity, this study will employ sophisticated phenotype assessment and statistical analysis methodologies to overcome these complications and in order to identify genes that contribute to this complex behavioral phenotype. To elucidate the genetic basis of dyslexia, the applicant proposes to: (1) To evaluate attention and executive function component phenotypes for suitability for genetic studies. (2) To localize genes that contribute to performance on quantitative measures of attention and executive function by genome-wide linkage analyses (3) To evaluate candidate genes which are implicated in attention networks for association with the identified component phenotypes of dyslexia (4) To refine the genetic loci identified in Specific Aim (2) The candidate's immediate career goal is to acquire the necessary skills to study complex genetic disorders. This training grant will allow the candidate to build upon his prior experiences in the molecular genetics of "simple" Mendelian disorders and afford the applicant the opportunities to (1) learn methods for understanding and dissecting complex cognitive/behavioral phenotypes, (2) acquire new molecular genetics skills pertinent to common genetic variations and complex phenotypes, and (3) attain new statistical genetics skills relevant to the study of complex genetics. These goals will be accomplished through formal didactic coursework and practical performance of laboratory, linkage and association studies. The candidate's longterm career goal is to study the etiology of complex psychiatric disorders that have varying degrees of genetic influences.